New ortho-hydroxyazo dye



Patented Oct. 6, 1925.

, KA TWA SSEE, 9 imm m, Henri-arm KI-RGHHOFF; or BERLINLIQHTEBFE13DE NHA S seem. at eeetqr eswea Gasman. Assi nee t 'A rIE s'ata cnerr rt. emiweaaxsarma I New Qew'sQ-sr m-Aw'p No Drawing.

To all whom it may concern:

Be-git known tliat wegk OSKAR KALT- 1VASSER, HERMANN KiRCHHOFF, and (3)HANS OEHRN, citiZensofYthe German. Republic, residing at (1) Berlin,Germany, (2) Berlin-Lichterfelde, Germany, and (3) Mommsenstr. 13,Charlottenburg, Germany, have invented certain new an usefulImprovements in New Ortho-Hydroxyazo Dyes, of which the following is aspecification.

According to this invention by combining a sulphonatedortho-hydroxydiazo compound with an unsulphonated 1-naphthyl 3-methyl-5-pyrazolone dyestuffs are obtained which are very Theafter-chromed tints or those obtained by dyeing in the presence of achromemordant have an excellent fastness to the action of light and tostoving.

The following examples illustrate theinvention but without limiting it,the parts being by weight:

1. 22.6 parts of l-p-naphthyl-3-methyl-5- pfyrazolone are suspended in225 parts of Water. At a temperature of 35' C. the diazo-compoundprepared in the usual manner from 23.5 parts of 2-amino-4-nitro-1-hydroxybenzene-G-sulphonic acid is added. After addition of 5.3 parts ofcalcined sodium carbonate the whole is stirred for6 to 8 hours. Thedyestuff is thus obtained for the greater part in the form of aprecipitate. It is finished in the usual manner; It dyes Wool in thepresence of chromium mordants orange tints. The dyestuff hasprobably'the formula:

CHI

2. A suspension of 22.6 parts of l-oz'v naphthyl-3-methyl-5-pyraz0lonein 225 parts of water is mixed with 29.5 parts ofnitronaphthalene-l.2-diazoxyde-4-sulphonic acidv valuable for dyeingwool. P

Application mees 15, 1925; Serial -no..:1ap,e1'e.1 1.

aaxisgfinaad. use. was. flyestufi=,;has probablytheformula The positionof the nitro group is unknown.

3. To a suspension of 22.6 parts of 1-5- naphthyl-3-methyl-5-pyrazoloneand 225 arts of water 46.7 parts of the barium salt of naphthalene 1.2dia-zoxyde 4.6 disulphonic acid .and 10 parts of calcined sodiumcarbonate are added. The mixture is stirred until the combination iscompleted. Acetic acid is added and the separated dyestuff is filtered.The chrome-lake of the dyestuflt' on wool is bluish red. The dyestuif inthe formof its free acid has probably the formula Dyestuffs formed bycombining a sulphonated ortho-hydroxydiazo compound with 1.t-naphthyl-3-methyl-5-pyrazolone in the form of their free aclds arerepresented by the general formula:

lVhat we claim is,-

1. The herein-described new ortho-hydrozya-zo dyes the after-chromedtints of which and those, obtained'by dyeing in the presence of achrome-mordantbeing orange to bluish red and having an excellent fastmethyl- 5 -pyraz olone.

2. The herein-described new ortho-hydroxyazo dyes the after-chromedtints of which and those obtained by dyeing in the presence of achrome-mordant being orange to bluish red and having ail-excellentfastness to the action of light and to stoving, the dyes manufactured bycombining a sulphonated ortho-hydroxydiazo compound with anunsulphonated 1.(3-naphthyl-3- 15 methy1-5-pyrazolone.

3. The herein-described new ortho-hydroxyazo dyes the after-chromedtints of which and those obtained by dyeing in the presence of achrome-mordant being orange to bluish red and having an excellentfastness to the action of light and of stoving, the dyes beingmanufactured by combining a sulphonated or-tho-hydroxydia-zo compoundWith 1.[5-nap:ththyl-3-methyl-5-pyrazolone. 1 I r I In testimony whereofWe affix our signatures.

Dr. Phil. 'OSKAR KALTWASSER. Dr. Ph. lug. HERMANN KIRCHHOFF. HANS OEHRNQ

